Still frowning, Fliss shook her head. ‘I can’t put my finger on it,’ she said, frustrated, and they all groaned. ‘But I’ve got a good memory for a face,’ she added. ‘And I’m telling you: I’ve seen her. It’ll come back to me.’

‘I’m just off to meet Dave for a round of golf. I’ll be back later, probably sometime this afternoon, unless we stop for a pint,’ John said after lunch on Saturday, halfway out of the door.

‘Right,’ Robyn said tonelessly. Not that he noticed her lack of enthusiasm, or the fact that she hadn’t called out to pass on her love to Dave, as she usually would. He was already gone, heaving his golf clubs into the boot of the car as if that was enough to convince anyone, before reversing out of the drive, then speeding away. Here we go again, she thought to herself. Going to play golf with Dave, indeed. Did Dave know about this, she wondered? Or would he, like Stephen, unwittingly blow John’s cover by turning up at the door later on, his alibi unprepared?

Well, bugger it. If John wanted to sneak around, then so could she. In fact, she’d already started. After the other night, when she’d known full well he had lied about going out with Stephen, Robyn had taken the liberty of installing a tracking app on her phone and had linked it to John’s. He had no idea that, any time she wanted, she could open the app and find out where he was. Like now, for instance, when, funnily enough, he didn’t appear to be heading in the direction of the golf course at all. In fact, according to the little map on the screen of Robyn’s phone, he was travelling in the opposite direction: up Fulford Road towards the city centre.

‘Harry, would you mind keeping an eye on the kids for a while? I’m just popping out to the supermarket,’ she called through to her father-in-law. Two can play at this game, John, she thought, grabbing her car keys. ‘Kids, be good for your grandpa, okay? Text me if there are any problems. I won’t be long.’

It was actually quite exciting starting up her engine and glancing down at the map to track John’s progress. Follow that car! Well, okay, so perhaps ‘exciting’ was the wrong word, she corrected herself. Setting off in pursuit of her lying husband, in the hope of catching him out, was more what you’d call nerve-racking than exciting. Did she really want to know John’s secrets?